1. Field of the Invention
The present invention relates to a receiving hopper or stacker for documents which is adapted to stack documents flat after they have been fed on edge along a document feedtrack.
2. Description of the Prior Art
In document handling machines, the documents, initially placed in a supply magazine, are extracted from the magazine one-by-one, are conveyed along a track consisting of rotary feed rollers and conveying bands, belts or endless chains, and are finally deposited in a receiving hopper. To allow the documents to be processed, the track is provided with functional members which perform recognized functions such as, for example, analyzing the markings carried by the documents, checking printed data, or apply fresh data. The number and nature of the functional members on the track vary depending upon the type of machine concerned.
In cases where the documents which are moved along the track also need to be visible to the operator, either to enable the reading of written data carried by the documents, or again to check certain markings made under the control of a keyboard operated by the operator, it has been found advantageous to arrange the track in such a way that it offers maximum visibility to the operator, that is to say it is arranged almost vertically, the documents on the track being then fed along on edge parallel to their length. As an example, a handling machine in which the track is so arranged is described in particular in U.S. Pat. No. 3,285,500. In this machine, the documents, after having been processed, are ejected into the receiving hopper where they are then stacked on edge, the stacking being performed by means of a suitable mechanism which pushes back the pack formed by documents which have already accumulated in order to make room for each document as it arrives in the hopper. However, this procedure is not entirely satisfactory in that, when the number of documents stacked in the hopper becomes relatively large, the pack so formed cannot comfortably be taken hold of in the hand and, this being the case, there is a danger that the operator, when he takes the pack out of the hopper will be unable to keep hold of it and will thus spill the documents over the ground.
To overcome this disadvantage, document stacking arrangements have been proposed, of a type similar to that which is, for example, described in U.S. Pat. No. 3,137,499, in which each document is fed on edge along a track and, after being diverted from its course in order to be fed to a receiving hopper, is introduced into a curved deflecting member where it is subjected to a turning motion so that it is in a substantially horizontal position at the time when it enters the hopper. An arrangement of this kind thus enables a pack of documents to be obtained which, since they are resting flat in the receptacle, can easily be taken hold of by the operator. However, the arrangement has proved expensive to construct in that, not only does the deflecting member have to be very carefully made by reason of its special shape, but it also has to be provided with additional and correctly orientated feed rollers so that each document introduced into the selecting member can be moved forward. In addition, because of the rubbing to which each document is subjected in the course of its passage through the deflecting member, the arrangement is often the cause particularly troublesome electrostatic effects which upset the operation of the machines into which the documents are subsequently introduced. These effects are all the more pronounced in that the documents are, in general, not very stiff and usually consist of punched cards, cheques, invoices and similar documents.